Automatic safety system for vessels containing liquid under pressure



y r c. s. MESSLER AUTOMATIC SAFETY SYSTEM FDR VESSELS CONTAINING LIQUID UNDER PRESSURE Filed May 24, 1924 & i k n lNVEN-TOR C/in/on 6.Ms.s/e/;

BY I z amp/00M ATTORNEYS Egg C. S. MESSLER AUTOMATIC SAFETY SYSTEM FOR VESSELS CONTAINING LIQUID UNDER PRESSURE May 3 1927.

Filed May 24. 1924 2 Sheets-Sheet 2 glvwentoz ClLbtanSMesslen Patented May 3, 1927.

UNITED STATES PATENT. OFFICE;

CLINTON S. MESSLER, OF BEACON, NEW YORK, ASSIGNOR TO THE GREEN FILTEIECONO- MIZER COMPANY, OF BEACON, NEW YORK, A CORPORATION OENEW YORK AUTOMATIC SAFETY SYSTEM FOR VESSELS CONTAINING LIQUIDIUNDER rnnssunn.

Application filed m 24, 1924. Serial No. 715,552.

' This invention relates to temperature and pressure control for vessels in. which liquids are heated, and its chief object is to provide for the purpose automatic means of simple and durable construction which will operate with unil'ailing reliability, thus obviating all danger of explosion due to excessive temperatnre. In its preferred form the inven tion' is designed for use with vessels, normally closed "from the atmosphere, through which a continuous iiow of liquid is maintained so as to be heated during its passage through the vessel, and in this class of apparatus the invention finds important application to fuel eco'nomizers for heating boiler feed-water. One form oi? the invention as designed for this purpose is illus trated in the accompanying drawings, in which Fig. 1 shows the'control system in a somewhat diagrammatic manner. c

Fig. 2 is a section illustrating a relief valve which can be used in my invention.

' Fig. 3 is a section illustrating a thermostatic valve suitable 1 01 my invention; I

Fig. 4.- is a diagrammatic side view, partly in longitudinal section, showing a steam boiler and a fuel econon'iizer for heating the boiler teed-water.

In the system illustrated in Fig. 4 the gases or products of combustion from the boiler furnace 1 are conduct-ed by a flue 2 to the econontizer 3, comprising vertical water tubes connected by transverse headers 11 to upper and lower longitudinally extending manifolds l. Having given up a portion of their heat to the water in the economizer the furnace gases pass to the stack 5. Hot water is delivered from the economizer to the boiler by pipe 12, having a hand-valve 13, and the usual check'valve G, employed in all economizer systems, to prevent flow of water or steam from the boiler to the economizer. \Vater is supplied to the econoinizer from any suitable source, notshown, by a pump '7. The connection between pipe 12 and the economizer may be conveniently made, for the purpose of the present invention, through a pair of Ts 14, 15. The first mentioned T houses a thermostat- 16, of any suitable type, which extends into the T and is therefore subjected at all times to the temperature of the water leaving the economizer. The other T 15, is connected by a valve 17, preferablyot the ated thereby in pipe 25.

balanced type, and pipe 18, to the hot-well or other storage receptacle, not shown. A suitable type of valve 17 is shown in Fig. 2, in which the two valve disks 19 are fixed on the valve stem 20 which is urged upwardly,

, to lift the disks oil their seats, by a spring 21. 7 The stem is connected to a diaphragm 22 spanning a chamber 23 having an inlet 24 for fluid under pressure by which the tension of the spring maybe overcome and the valve held closed, as will be readily understood.

The fluid pressure inlet 24 of diaphragm valve 17 is connected by a pipe 25through a valve 26 to the fuel econoinizer outlet T so that the outlet pressure in the economizer can be communicated. to the diaphragm.

The inlet 24 is also connected, by pipe 27 through a valve 28 to the steam line or other source of fluid pressure which may be utilized at will to apply pressure to the diaphragm for closing valve 17. The two valves 26 and 28 are preferably of thegate type, and are actuated by thesame stem 29, which, for the purpose'ott control from a remote point, may be provided with a sheave 30 connected by a belt 31 to an actuating device (as for example a hand-wheel, not shown) located at a convenient position. These valves 26 and 28 are also assembled for opposite operation, that is, so that as one is opening the other is closing, and' vice versa.

The pressure exerted v.on the -diaphragm 22 of Valve 17 is controlled automatically by the thermostat 16,"and valve 32 actu The thermostat may be ofany suitable type, but I prefer one of the expansibletluid class, in which the expansion and contraction of a'fluid in response to changeof temperature is utilized to actuate a piston or equivalent device. Thermostats of this type are well known andt'urther description thereof is therefore unnecessary. Vith such a thermostat it is advantageous to make the valve 32 one of the piston-actuated balanced type, fore ample as illustrated in Fig. .3. In this figure the valve is normally held'open by a spring 33, and is closed against the tension of the springs "(which can be regulated by the threaded plug 34) by the stem 35 and piston 36 upon which the fluid pressure transmitted by the tube 37 from the thermostat 16 is exerted. The opening 38 through which the stem works is sealed by the sheet metal bellows 39, hermetically joined to the piston at the top and to the valve casing at the bottom. The piston and bellows are housed in a cylindrical casing d0. In the side of the valve casing is a vent all, and in the stem 85 is a passage a2 which is broughtinto register with the vent when the valve is closed, thereby putting the diaphragm chamber 23, Fig. 2, into communication with the atmosphere, as will be readily understood.

The system illustrated operates as -lollows: Under normal conditions water from the economizer (heated in its passage therethrough) is flowing to the boilers by way of pipe 12, valve 28 is closed and valves 26 and 32 open. The pressure in the economizer 1s therefore transmitted through pipe 25 to the valve diaphragm 22 and valve 17 is held closed. 11, now, the temperature in the economizer rises above the predetermined point (the thermostatbeing properly adjusted) at which vaporization in the economizer becomes dangerous the valve 32 closes. This cuts oil the pressure on valve diaphragm 22, Fig. 2, and vents the diaphragm chamber 23 to the atmosphere by way of passages all and 42, Fig. 3, thereby relieving the pressure on the diaphragm and permitting spring 21 to open valve 17. Pipe 18 to the hot-well is thus opened, and through it the economizer is vented, reducing the pressure therein at once and at the same time allowing more water to flow through it, which in turn reduces the economizer temperature. On the other hand, assuming the conditions to be normal, as first described, suppose that the economizer pressure is reduced below the point necessary to keep valve 17 closed, as may happen it the pump (not shown) which passes water through the QCOIlOll'llZGI, should stop. Valve 17 then opens, and vents the economizer to the atmosphere through pipe 18 as previously described. The economizer then becomes an open vessel, and gene ation of steam therein cannot raise the pressure to the danger point. Valve 17 having been opened by increase of temperature or decrease of pressure in the economizer, it can not be closed again except by a manual operation, thus making it certain that the condition oi the apparatus will be brought to the attention oil the attendant. To close valve 17 the sheave 30 is rotated, closing valve 26 and opening valve 28. The latter then admits sutlicient pressure (from the steam line, for example) to diaphragm chamber 23 to close the valve against the tension of sprin 21. lVhen it is judged that the economizer pressure has been restored to normal the valve 28 is closed and valve 26 opened, thereby restoring the system to normal condition. If, however, the

economizer pressure had not reached a value high enough to keep valve 1? closed, the latter is at once opened again as already described. Similarly, the same thing happens it the economizer temperature has not been reduced to normal, as will be readily understood, since valve 32 will not have been opened and hence the economizer pressure through pipe 'annot be transmitted to the diaphragm. The usual economizer safety 'alve is indicated at l3.

It is to be understood that the invention is not limited to the specific construction here-- in illustrated and described, but can be embodied in other forms without (:leparture from its spirit.

I claim-- l. The combination with a normally closed container for heating a liquid, ot a reliel valve therelor, automatic means for opening the relief Valve, means for utilizing the internal pressure of the container to hold the relief valve closed in opposition to said automatic means, and telnperature-controlled means operable independently ot the level of the liquid in said container for disabling said pressure utilizing means when the internal temperature of the said container rises to a predetermined point.

2. The combination with a normally closed container for heating a liquid, ol a relief valve therefor, a spring under tension to open the valve, pressure-actuated means to close the valve against the tension of said spring, a pipe connecting the container with the pressureaetuated means for actuation thereof by the internal pressure of the container, a normally open valve in said pipe, and thermostatic means responsive to the temperature in the container for .closing said normally open valve whereby the pres sure on the relief valve closing means is cut ofli.

3. The combination with a normally closed container for heating a liquid, of a reliel valve for the container, means tending to hold said relief valve open, and means arranged to operate above a predetermined pressure and below a predetermined tem perature in the container to overcome the first mentioned means and hold the valve closed.

at. The combination with a normally closed container for heating a liquid, ol a relief valve for the container, automatic means for opening the relief valve, pressure operated means for utilizing the internal pressure of the container above a predetermined value to hold said relief valve closed in opposition to said automatic means, and means for cooperating with said pressure operated means for closing the relief valve after the same has been opened by said automatic means, said means for coo perating including a manually operable member.

5. The combination with a normally closed container for heating a liquid, of a relief valve therefor, automatic means for opening the relief valve, means for utilizing the internal pressure of the container to hold the relief valve closed, temperature-controlled means for disabling said pressure utilizing means when the internal tempera ture of the said'containcr rises to a predetermined point, and means for cooperating with said pressure operated means for closing the relief valve after the same has been opened by said automatic means, said means for cooperating including a manually operable member.

6. The apparatus described in claim '2, in combination with manually controlled means for applying pressure from an external source to the pressure-actuated means, whereby to close the relief valve after the same has been opened by the spring.

7. The apparatus described in claim 3, in combination with means for closing the relief valve, the last mentioned means including a manually operable member.

8. The combination with a fuel econo- HilZQl having a water outlet, of a relief valve connected with the said outlet, means tending to hold said reliefvalve open, and means arranged to operate above a predetermined pressure and below a predetermined temperature in the economizer to overcome the first mentioned means andhold the valve closed.

9. The combination with a fuel economizer having a water outlet, of a relief valve connected with the outlet opening and having a spring under tension to open the valve, pressure-actuated .means for closing the valve against the tension of the valve spring, a pipe connecting the pressure-actuated means with the econoinizer for actuation by the pressure therein wherebythe relief valve is normally held closed but is permitted to open when the economizer pressure falls to a predetermined value, a normally open valve in said pipe, having means'for venting the pressure-actuated means when the said normally open valve is closed, and thermostatic means responsive to the tempera ture in the eeonomizer to close the normally open valve and vent the pressure-actuated means when the economizer temperature rises to a predetermined value.

10. The apparatus described in claim 9, in combination with manually controlled means for closing said pipe and applying pressure from an external source. to said pressureactuated mechanism.

11. In a system for the purpose described, in combination, a normally closed container for heating a liquid, a relief valve for the container, nessure-operated means to hold said valve closed, and means arranged to operate at a predetermined temperature to overcome the pressure-operated means and open said valve.

In testimony whereof Ihereto afiix my CLINTON S. MESSLEB.

signature. 

